Page 40 - D. Raleigh "Knots and ropes for climbers"

Mule Knot.

Munter Mule

If you're belaying or rappeling with the Munter Hitch, you'll need the Munter Mule if you are to tie
off the rope and free your hands. The Munter Mule is simply a Mule Knot tied on the standing side of
a Munter Hitch. Before you tie the Munter Mule, be sure the rope is taut; a slack rope can cause you to
orient the knot in the wrong direction. Tie the Munter Mule around the active (loaded) side of the rope,
and do not pass a bight of rope through the belay/rappel carabiner before tying the Munter Mule. Clip
a carabiner through the Munter Mule's open loop to prevent it from slipping, or use the Overhand
backup as discussed with the Mule Knot.

Common Use
Tying off lead or rappel rope to free your hands

Mariner Knot

The Mariner Knot, illustrated on page 56, is a complex, exotic knot that, like the Mule Knot and
Munter Mule, is releasable when under load. Unlike the Mule and Munter Mule, however, you do not
tie the Mariner Knot in the lead or rappel rope. Rather, you take a loop of 9/16-inch webbing and wind
this around a carabiner, and then around the loop itself. The common use of the Mariner Knot is to